<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8" />
		<title></title>
		<link rel="shortcut icon" href="img/favicon.ico">
		<style type="text/css">
			* {
				margin: 0 auto;
				padding: 0;
				font-size: 30px;
				border-radius: 20px;
			}

			header {
				width: 1200px;
				height: 100px;
				background-color: skyblue;
				margin-bottom: 10px;
			}

			footer {
				width: 1200px;
				height: 100px;
				background-color: blue;
				margin-top: 10px;
			}

			.main {
				width: 1200px;
				height: 700px;

			}

			.main div {
				float: left;
			}

			.main .main_left {
				width: 290px;
				height: 100%;
				background-color: orangered;
				margin-right: 10px;
			}

			.main .main_center {
				width: 590px;
				height: 100%;
				background-color: red;
				margin-right: 10px;
			}

			.main .main_right {
				width: 300px;
				height: 100%;
				background-color: yellow;
			}
		</style>
	</head>
	<body>
		<header>网页头部 1200 * 100 px</header>
		<div class="main">
			<div class="main_left">左边300*700px</div>
			<div class="main_center">中间600*700px</div>
			<div class="main_right">右边300*700px</div>
		</div>
		<footer>网页尾部 1200 * 100 px</footer>
	</body>
</html>
